Which amp to buy? ARC GS150 or Reference 150 SE?

"I like the meters on the ARC GS150 (easier for bias adjustments) but the Reference 150 has no meters. How much of a pain is it to bias the Ref 150? Do I need an external meter to bias the Ref 150?"

Meters or no, always use a multimeter to set bias. Besides, how would you be able to use the front meters anyway? All the tubes are connected to them. I believe on the 150 you only set bias for half the number of tubes in the amp. One bias adjustment does 2 tubes. Regardless, just buy the amp that sounds the best. Setting bias is a simple matter, and there's really reason include the adjustment as part of your purchase decision.

More important is your choice of preamp. The Ref 150 only operates balanced so you want to make sure you match it with a preamp that will give you the best sound quality and no problems. Personally, if it was my system, I would use an ARC preamp.

What speakers do you plan to use?

"Every time I go back to my Conrad Johnson gear, it makes me realize how good it sounds. I do like the variety of different gear, but never lived with ARC. A friend had it and it was great but can not comment on how it differed from my CJ gear because the systems were totally different. I do feel that my CJ gear is a touch sweeter, which I love. The ARC gear may be more of an experiment but have other friends that swear by it."

I've had several pieces from both brands and while they sound different from each other, both are excellent. For me personally, if I was to go with ARC, I would use a matching amp and preamp, or an amp with a fully balanced source with its own volume control, like my Wadia CD player.